After 22 years in law enforcement, John Moore has seen a lot. But the veteran Wake County, North Carolina Sheriff's investigator says a recent case is one of the most satisfying of his career.

The parents of a 14-year old boy contacted a friend at the sheriff's office about a 47-year-old New York man who had been communicating online with their son for six months.

It was all innocent enough -- an internet community buying, selling, and trading sports memorabilia online.

Moore investigates child sex crimes and knows even the most innocent activity is utilized by child sex predators.

"Trading and selling sports memorabilia which is something, obviously, that a lot of children and youth are interested in," he told ABC 11.

The boy's parents learned the man was going to travel all the way from Saratoga County, New York to Raleigh for a December sports memorabilia show at the State Fairgrounds in Raleigh.

He wanted to meet the boy.

Red flags went up.

Although the boy never went to the show, Moore says the man from New York, Gary Ryan, managed to pull off a brief meeting with the boy without the knowledge of the boy's parents.

The only physical contact was a handshake.

A short time later, the boy told his parents that Ryan had contacted him to say that he was returning to New York but had left a present for the boy with the desk clerk at a North Raleigh hotel.

Curious, the boy's parents escorted him there.

"And sure enough there was about $2,000 worth of sports memorabilia that he had left there for this 14-year-old," Moore said.

Even more red flags went up.

A friend found an old listing for Ryan on the Florida sex offender registry involving children.

That's when the family reached out to the sheriff's office.

Moore said he soon found out that Ryan was actually in New York and listed on a sex offender registry there that was not public.

He contacted a detective at the Saratoga County Sheriff's Office, and said he was calling about Gary Ryan.

"As soon I mentioned his name, he stopped me. And he said, 'Hold on a second. I'm going to tell you what he did.' I said, 'Okay.' He said, 'Let me guess. Thirteen, 14-year-old boy, sports memorabilia, trading online.' I said, 'Yes, sir.' He said, 'That's him. What did he do because I want him.'"

Soon the FBI also called Moore saying they too were investigating Ryan.

Moore said the FBI had an idea on how to catch him.

"As long as he thought he was still talking to somebody he's been talking to for six months, it was the best bet to try and get him. So they took over his identity," he said.

The North Carolina boy's parents granted permission for investigators in New York to assume the child's online identity.

The investigators began communicating with Ryan.

Soon they had enough evidence to raid Ryan's home and arrest him on five felony child sex charges.

After the raid, the Saratoga County detective called Moore.

"He said he heard something he's never heard before from the agent, from the FBI who said, 'This is the real deal. This guy's a monster.'"

Moore is being praised by his fellow investigators, but says the credit goes to the child's parents who closely monitored their son's online activity.

"That family having the courage to come to us on something that may or may not have been a big deal to some people, turned into something where we just saved many victims in the future. So it felt great," he said.

Although there is no evidence a crime was committed in North Carolina you can bet Moore will continue to closely follow the case in New York where he says federal charges are also now pending.